Authentication for storage queries

Most substrate chains are entirely transparent and everyone has read access to all the storage.
Privacy focused chains, like the Integritee privacy sidechains, on the other hand, only authorize queries based on authentication. (Only the owner of an account can query their own balance)
Apart from that requirement, all else could work like normal substrate rpc.

For easy integration and compatibility with wallets, we suggest to specify authentication for storage queries here.

The node may also define "view keys" (similar to how the proxy pallet works), so we can't generally assume that the authorization is restricted to the signer's own account. Also, some storage may not require authentication, like total supply of tokens or the block number)

It is not yet clear to me, what the best procedure would be for this spec, which are easy to implement for wallets. looking forward to ideas here.

Start by reviewing the issue discussion and the existing substrate RPC behavior described there. Work out and document a wallet-compatible procedure for authenticated storage queries, including view keys and storage that remains public. Done means the specification has an agreed authentication model and clearly defines which queries require authorization.